Dental impression-tray.



- M; ACKERMAN. DENTAL IMPRESSION TRAY."

APPLICATION FILED FEB. 3 i916.

1 1 99,647 Patented Sept. 26, 1916.-

Inventor Attorneys MAURICE ACKERMAN, on NEW Y RK, N. Y.

DENTAL IMPRESSIONi-TRAY. I

Specification of Letters Patent.

PatentedSept. 26, 1916.

Application filed February 3, 1916. SerialNo. 75,999.

To all whom it may concern:

Be itknown that I, MAURICE AOKERMAN, a citizen of the United States,residing at New York, in the county of New Yorkand- State of New York,have invented a new and useful Dental Impression-Tray, of which thefollowing is a specification.

This invention relates to dental impression trays, one of its objectsbeing to provide a tray formed in one piece and which has a novelarrangement of ribs whereby grooves are formed in the impression andwhich grooves are so located that the impression can be brokentherealong into five pieces all of which are practically straight sothat no difliculty will be experienced in separating them from theteeth.

A further object is to provide the tray with a retaining lip upon thepalatal portion whereby soft plaster is prevented from flowing into thethroat of the patient.

With the foregoing and other objects in view which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes in the preciseembodiment of the invention herein disclosed, can be made within thescope of what is claimed, without departing from the spirit of theinvention.

In the accompanying drawings the preferred form of the invention hasbeen shown.

In said drawings :Figure 1 is a plan view of the tray. Fig. 2 is acentral vertical section therethrough. Fig. 3 is a rear elevation.

Referring to'the figures by characters of reference 1 designates thebase of the tray, the same being of substantially the usual 7configuration and having a handle portion 2 formed integral therewithand provided with an opening 8 whereby it can be suspended readily froma nail or the like. Extending from this base portion is a flange 4following the curved margin of the base and inclined relative to saidbase. Formed on the inner face of the flange 4 is a central rib 5 and ateach side of this central rib is a side rib 6. These ribs 5 and 6 extendup to a curved rib formed upon the base of the tray and which isparallel with the flange or wall 4:, said rib being indicated at 7Formed along the palatal portion of the base is a retaining lip 8. It isto be understood that the flange or wall 4 is to be properly shaped tofit comfortably within the mouth so as to accommodate the levator labiisuperioris and the condyles. In using the trayit is filled with theplaster to be used in making the impression and is then pressed againstthe teeth so that the teeth will become embedded in the plaster atpoints close to the flange or wall 4. The lip 8 will prevent theplaster, if soft, from flowing into the throat of the patient andcausing discomfort. Afte the plaster has become set the tray iswithdrawn therefrom and the ribs 5, 6 and 7 will leave grooves in thefront, sides and bottom of the plaster cast. By forcing the nails of thefingers into the grooves the cast can be broken therealong into fivedifferent sections, to wit, two sections on each side of the center anda base section bounded by the grooves formed by rib 7. As four side.

sections are produced each of them will be approximately straight sothat it can be removed easily from the teeth without crumbling, thusenabling a perfect impression to be retained.

The lip 8 not only serves to prevent plaster from flowing into thethroat of the patient but also serves as a gage for the operator. Whilethe impression is being taken the operator first presses the backportion of the tray into position and should the tray be pressed too farthe impression would come out too thin and break easily. With the lip 8,however, the operator can only press down as far as this lip will permitand when the impression is taken out it will be of uniform thickness andnot so easily broken by handling.

It will be noted that the entire tray is formed in but one piece so thatit can be easily kept sanitary and there are no parts likely to becomedisplaced in handling.

It will be noted that the walls of the tray are so shaped as toaccommodate the muscles in the vestibule of the mouth and the condylesall of which is important in the making of a perfect fitting plate. The

base, there being a retaining lip along the palatal portion of the baseand constituting a gage, there being a curved rib parallel with the wallof the tray and upon the base,

and additional ribs upon the inner surface of the wall of the tray, oneof said ribs being arranged at the center of the Wall and extending fromthe free longitudinal edge thereof downwardly to the rib on the base 10and the other ribs being extended down- MAURICE ACKERMAN.

Witnesses:

7M. H. KRUsE, JOHN L. PETERS.

Gopies of this patent may be obtained for five cents each, .byaddressing the Commissioner of Patents,

- Washington, D. 0.

